Human cytomegalovirus (HCMV) is a widespread pathogen of growing medical importance HCMV is an opportunistic pathogen in AIDS patients, transplant recipients and is also the leading cause of virally induced birth defects Based on the significant threats posed by HCMV, the overall goal of this research is to provide a more complete understanding of HCMV replication More specifically, the proposed research will explore the hypothesis that a 5kb immediate early transcript functions in the capacity of an RNA molecule Two research aims are outlined in this proposal (1) characterize the synthesis, structure and localization of the 5kb transcript and (2) further explore the function of transcripts derived from the 5kb region by constructing a viral mutant Detailed characterization of the function of the 5kb transcript will provide the opportunity to understand HCMV replication as well as illuminate aspects of cellular biology and possible allow development of therapeutic interventions for HCMV infection.